Centrifugal casting machine with shuttle car operating between arranged work stations



May 7, 1968 R. w. TACCONE 3,381,744

CENTRIFUGAL CASTING MACHINE WITH SHUTTLE CAR OPERATING BETWEEN ARRANGED WORK STATIONS 3 Sheets-Sheet 1 Filed Oct. 23, 1965 m/ssaz. m mam/v5 m m P 0 n 4 May 7, 1968 R W. TACCONE CENTRIFUGAL CASTING MACHINE WITH SHUTTLE CAR OPERATING BETWEEN ARRANGED WORK STATIONS Filed Oct. 23, 1965 3 Sheets-Sheet 2 /ZZ A34 INVENTOR RUSSELL W TACCONE BY%@IMM ATTOE/VEYS May 7, 1968 R. w. TACCONE CENTRIF'UGAL CASTING MACHINE WITH SHUTTLE CAR OPERATING ,BETWEEN ARRANGED WORK STATIONS 3 Sheets-Sheet 3 Filed Oct. 25, 1965 INVENTOR.

P055511. MA MCC'OA/' BY Z Unit This invention relates to centrifugal casting machines, and more particularly to machines for the casting of pipe.

The general object of the present invention is to improve centrifugal casting machines, and more particularly to improve the centrifugal casting of soil pipe. In usual practice a core is set in one end of the mold, the mold is spun, the molten metal is poured, the mold and resulting pipe are cooled, the solidified pipe is pullled from the mold, and the inside of the mold is sprayed with a suitable protective coating. To spin the mold it rests on motor driven spin wheels.

In accordance with more specific features and objects of the present invention the mold, or preferably a pair of collateral molds, are mounted on a shuttle car which is shuttled between a pouring station and a pulling station. Either position of the car also may be used for core setting, and the pipe pull position of the car is also used for spraying the interior of the mold. By using two cars and two pulling-stations the output of the machine is nearly doubled, because the pulling of the two pipes and the spraying of the two molds takes place at the same time that another two pipes are being spun and cast at the pouring station. One pouring station serves for both pulling stations.

To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, my invention resides in the centrifugal casting machine elements and their relation one to another as are hereinafter more particularly described in the following specification. The specification is accompanied by drawings in which:

FIG. 1 is a plan view of a centrifugal casting machine embodying features of the invention;

FIG. 2 is an elevation thereof;

FIG. 3 is an end elevation looking toward the left end of FIG. 1;

FIG. 4 is an elevation like FIG. 2 but drawn to larger scale and showing only the shuttle cars;

FIG. 5 is a partially sectioned plan view of the shuttle cars drawn to still larger'scale and omitting the molds;

and

FIG. 6 is a section through a mold.

Referring to the drawings and more particularly to FIGS. 1 and 2, the machine comprises a shuttle track generally designated 12, with two shuttle cars 14 and 16 thereon. There is an automatic core setting station 18, which is schematically indicated in FIG. 1 but omitted in FIG. 2, this being located at one side of the track 12 midway between the ends. A pour station generally desig nated 20 is located at the other side of the track 12 at a point opposite the core setting station. There are two pulling stations generally designated 22 and 24 on one side of the track 12, one near each end, and two spray stations generally designated 26, 28 (FIG. 1) on the other side of the track 12, at points opposite the pipe pulling stations 22 and 24 respectively.

Each shuttle car has a pipe mold 30 resting on spin wheels 32 and 34. In practice the operation preferably is doubled, and another spin wheel 36 is provided, receiving a second mold 40 which is collateral to the mold 30, and which rests on the spin wheels 32 and 36. In such case the core setting station 18, the pour station 20, the

States Patent 0 3,381,744 Patented May 7, 1968 See pull stations 22 and 24, and the stray stations 26 and 28, all are double stations for simultaneous operation on the double molds 30 and 40 on the shuttle car.

The spin wheels 34 and 36 may be idle, while the spin wheel 32 is driven, in this case by means of a motor 42and a multiple V-belt drive 44. A silent chain may be used instead of V-belts. As usual, and as shown in FIG. 1, the molds rest on two spaced sets of spin wheels, the spaced wheels being indicated in FIG. 1 at 33, 35, 37, the wheel 33 being mounted on the same shaft as and being driven in unison with the wheel 32, and the wheels 35 and 37 being idlers.

It will be understood that car 14 is similar to car 16, and has motor driven spin and idler wheels carrying a pair of molds as described for car 16. As here illustrated the cars are moved independently by means of long hydraulic cylinders 118 and 120. The cars might be joined, that is a single large shuttle car means could be shuttled between stations, but for reasons explained later it is preferred to employ two separate cars which are independently movable. It will also be understood that a single pull and spray station could be located at the middle of the track, and duplicate core setting and pouring stations could be located at the ends of the track, but it is preferred to employ the present arrangement because it is better to use the molten metal continuously rather than intermittently; because the present arrangement clears the way for discharge of the finished pipe by rolling the same on inclined tracks indicated at 46 and 48 without interference by core setting stations; and because the pipe pulling operation is sometimes stalled by a difficult eX- traction, and with a single pipe pulling station that would disable both pouring stations, whereas with the present arrangement at least one side of the machine may continue in operation while the difficulty at the other pull station is being overcome.

The pour station 20 is shown in the background in FIG. 3, as well as in FIG. 1, and comprises boots 50 which are tiltable between a down or retracted position shown in FIG. 3, and a raised or pouring position shown in FIG. 6. The station also comprises ladles 52 (FIGS. 1 and 3) which are pivotally mounted and which may be raised from the horizontal position shown to be a tilted position which discharges molten metal into the boots and thence into the spigot ends of the molds. This mechanism is not described in detail because it forms a part of my companion application Ser. No. 502,918, filed on even date herewith, entitled Pouring Mechanism for Centrif ugal Casting Machine.

The ladles 52 act as measuring ladles for the desired quantity of molten metal. For this purpose the metal maybe measured by weight, and an alarm may be sounded when the ladle, then in a horizontal position shown in FIG. 3, has received from a holding ladle 54 (FIG. 1) the predetermined weight of metal.

Referring now to FIG. 6, the mold 30 has spin bands 56 and 58 which rest on the spin wheels. The pipe diameter may vary widely, say all the way from two to eight inches in diameter, and the spin bands are large enough for the largest mold. The smaller molds have spin bands with the same outside diameter, so that the mold axis is in the same position despite changes in pipe diameter. One of the bands, in this case band 56, has flanges 60 to hold the mold against axial movement. In a typical case the pipe may be four inch soil pipe having a length of five feet, in which case the bands are say three feet apart, or in another case the pipe has a length of ten feet, with bands say six feet apart.

The spigot end 61 of the mold is partially closed by a permanent dam 62, designed to confine molten metal to more than the desired thickness of the pipe 64. The bell end 66 of the mold receives a destructible sand core 68 which confines the molden metal and which shapes the bell end of the pipe. The core 68 is held in position by any of a number of known means which need not be described here. The mold is stationary during insertion of core 68, and it is then accelerated rapidly to full spin speed, whereupon molten metal is poured through boot 50 into the mold until the measured charge of metal has been supplied.

Meanwhile the molds are being cooled, and referring to FIG. 2 a hood 72 is located over the car to remove steam. Cooling spray pipes, in this case four pipes 74, are located over the molds and are supplied with cooling water through a pipe 76. The hood and pipes are omitted in FIG. 1 to better show the shuttle car. Water collects in the pump or pit 106 for removal or recirculation. This cooling may be continued during the full operation, and for that purpose each car may be provided with additional cooling pipes supplied through a flexible water hose. These pipes are suggested at 77 in FIG. 4, located beneath the molds, to spray water upward, but are omitted in the other figures of the drawing.

Referring to FIG. 3, the pull station 22 has horizontally movable pull heads 80, independently moved by separate long hydraulic cylinders housed at 82. Each head is carried by a bracket 81 secured to a fin plate 83 which moves beneath tube 82. An expansion shoe 84 is tilted inside the end of the pipe to grip the pipe under control of a small air cylinder 86, supplied through a flexible air hose, not shown. The pull head moves toward and into the mold (then no longer rotating), and during the pull the mold may be held back by stop means of any known type. This may be operated by means of an air cylinder supplied through a flexible hose (not shown) leading to the shuttle car. The mold anyway is held against axial movement by the flanges 60 (FIG. 6). The expansion shoe breaks through the sand core. It may be designed to grip inside the bell instead of inside the pipe beyond the bell.

The pipe which is extracted from the mold is pulled over raised pipe supports 90, which may be of known type, and which may have rollers over which the pipe passes. The pipe may be stopped by a stop 88. The supports are pivoted and act as lowering means which lower the pipe onto the inclined tracks 46 previously referred to in FIG. 1. I

The mold spray station also is shown in FIG. 3, it comprising a pair of parallel and preferably tubular lances 92 carried by a bracket 93 secured to a fin plate 94 which is moved horizontally by means of a long hydraulic cylinder housed at 96. The lances 92 are coaxial with the molds, and have spray heads at their free ends. If desired they may be additionally supported by yieldable rollers indicated at .98. A supply of a suitable mold coating material, is supplied through a flexible hose (91 in FIG. 3) connected to the rear ends of the lances. The liquid is supplied under pressure, and in a typical case may have silica flour and bentonite suspended in water. The mold is spun during the coating operation, and again is stopped when the core is applied, and spun when the metal is poured.

The pull and spray stations 22 and 26 (and their like companion stations 24 and 28 shown in FIG. 1) need not be described in greater detail, because they form the subject of a companion patent application Ser. No. 503, 942, filed on even date herewith, and entitled Pull and Spray Station for Centrifugal Casting Machine."

The shuttle cars may be described in greater detail with reference to FIGS. 4 and 5 of the drawing. They are massive and heavy in construction. Each car is supported on four horizontal rollers which ride on two spaced main support rails 102, which in this case are slightly higher than the floor level (indicated at 104 in FIG. 3). However, the heavy steel frame supporting the rails 102 is carried in a heavily lined concrete pit 106 the bottom of which provides a strong foundation or bottom at 108 (FIGS. 2 and 3).

FIGS. 3 and 5 also show how the cars are each provided with two guide rollers 110 which rotate on vertical axes and which are received in a guide track 112 which is sturdily built into and supported by the main track frame, and which holds the cars against lateral movement.

In FIG. 5 the four horizontal spin molds are omitted, and the left car 16 is cut away at the top to expose the spin or drive motor 42. The motor is energized through a flexible cable, not shown. The motor is located beneath the center spin rollers, as shown in FIG. 4, and carries a multiple V-groove pulley 114 (car 16 in FIG. 5) driving multiple V-belts 44 which drive V-groove pulleys 116 (see car 14 in FIG. 5) on the shaft 31 which carries the driven spin wheels 32 and 33. The other spin wheels 34, 35, 36, and 37 are idlers.

The cars are moved by long hydraulic cylinders. Referring to FIGS. 1 and 2, car 14 is moved by hydraulic cylinder 118, and car 16 is moved by hydraulic cylinder 120. These cylinders are disposed in the pit 106 and are mounted on top of cross members 122 (FIGS. 3 and 4) of the sunken frame of the machine. Car 14 has a depending arm 124 (FIG. 4) to which the piston rod 126 of cylinder 118 is connected. Similarly car 16 has a depending arm 123 to which the piston rod 130 (FIG. 4) of cylinder 120 is connected. It will be seen that the cylinders are long enough to shuttle the cars between the desired end positions, that is, car 16 is advanced in FIG. 4, and can be retracted to the broken line position 16, at which time the car is largely over its cylinder 120. Similarly the car 14 has already been retracted from the position now occupied by the car 16, and car 14 is shown disposed largely over its cylinder 118.

Because of its great mass the car is preferably brought to a gradual stop at each end of its travel by appropriate cushioning means. For this purpose car 114 has two dependent bumpers 132 which generally resemble the arm 124 previously referred to, but the bumpers 132 are at the other or outer end of the car, and there are two of them which straddle the cylinder 118, as will be seen in FIG. 3. These bumpers 132 engage stops 134 (FIGS. 3 and 4), which may be cushioned by means of oil cylinders or dashpots. Air or compression springs may be used to return the pistons of the dashpots. The cushioning stops 134 bring the car to a positive stop in exact desired. station location, but they engage the car somewhat ahead of the station position, and then cushion the stop action, without rebound.

A similar but oppositely directed pair of stops 136 (FIG. 4) is provided to engage the same bumpers 132 when the car 14 has reached the middle or pouring station. The cushioning stops .136 do not obstruct the main arms 124 and 128 previously referred to, the latter being disposed between and therefore clearing the sidewardly spaced stops 136. The latter are engaged by the inner or right face of the bumpers 132, as viewed in FIG. 4.

In similar fashion the outer end of car 16 has spaced bumpers 138, the outer faces of which engage spaced cushioning stops 140 when the car has been moved to its retracted or outer position 16, the bumpers then being at 138'. The inner faces of the same spaced bumpers 138 engage cushioned stops 142 when the car has moved from pull position 16, to the pour position .16, as shown by the solid line position of the bumpers 138. Here again the stops 142 do not interfere with either arm 128 or arm 124, because the stops are offset sidewardly, and are astride the path of arms 128 and 124.

This relation is also shown in FIG. 5, in which car 16 has bumpers 138 astride the piston rod 130, the latter being connected to the dependent arm 128, and car .14 has bumpers 132 which are astride the piston rod 126, the latter being connected to car 16 by means of its depending arm 124.

The use of two independent cars instead of one big car is preferable because the high speed spin of the molds is sensitive, and the pull when extracting a pipe is very forceful, and if applied to the same car might disturb the high speed centrifugal spin of the other molds. With separate cars the extraction pull at one car is largely insulated from the spin at the other car. There is also the advantage of flexibility in timing the operation of the machine because the cars can be moved somewhat differently in time instead of exactly in unison. There is also a practical advantage in that if one car should break down the machine may be used for half the normal output by using the other car alone. Moreover, in the event of sticking of a pipe in a mold at the pull station, with consequent delay in completing the pull operation, the other car can continue its operation while surmounting the difiiculty.

As so far described, it is assumed that the core setting station 18 (FIG. 1) is disposed at the middle of the shuttle track, opposite the pouring station 20. This is a preferred location if the core setting station is an automatic station operating at high speed. However, if the cores are set manually they may be set at the two pulling stations 22 and 24, and indeed that is preferred, because ordinarily more time is needed to pour and cool the pipe at the pouring station than is needed to pull the pipe and coat the mold at the end stations. The extra time is better utilized for manual core setting at the pulling station, instead of slowing the overall production rate by manually setting the cores at the station 18. However, with automatic core setting the middle station 18 is preferred because of the room available for the necessary mechanism, and also with automatic core setting the time required is minimized.

It is believed that the construction and operation of my improved centrifugal casting machine, as well as the advantages thereof, will be apparent from the foregoing detailed description. Inasmuch as one pair of pipes is being pulled and the molds are being sprayed while at another station a pair of molds is being spun and poured, the cycle time needed to produce each pair of pipes is cut substantially in half. The only loss is the travel time, which takes only a few seconds.

It will be apparent that while I have shown and described my improved centrifugal casting machine in a preferred form, changes may be made without departing from the scope of the invention, as sought to be defined in the following claims.

I claim:

1. A centrifugal casting machine comprising a shuttle track with shuttle car means thereon, a first station having metal pouring means at one side of the track, a second station comprising pipe pulling means on one side of the track and a mold spray means on the other side of the track at a point opposite the pipe pulling means, one station being midway between the ends of the track, the other station being near one end and being duplicated near the other end, the shuttle car means having spaced molds resting on spin wheels and having motor means to drive the spin wheels, and means to shuttle the shuttle car means on the track between a first and a second station.

2. A centrifugal casting machine comprising a shuttle track with shuttle car means thereon, a first pair of stations comprising a core setting station at one side of the track and a pouring station at the other side of the track at a point opposite the core setting station, a second pair of stations comprising a pulling station on one side of the track and a spray station on the other side of the track at a point opposite the pulling station, one pair of stations being midway between the ends of the track, the other pair being near one end and being duplicated near the other end, the shuttle car means having spaced molds resting on spin wheels and having motor means to drive the spin wheels, and means to shuttle the shuttle car means on the track between the core set-pour stations on the one hand and the pull-spray stations on the other hand, so that four of the six stations are in use at a time.

3. A centrifugal casting machine comprising a shuttle track with two shuttle cars thereon, a first station having metal pouring means at one side of the track, a second station comprising pipe pulling means on one side of the track and mold spray means on the other side of the track at a point opposite the pipe pulling means, one station being midway between the ends of the track, the other sta tion being near one end and being duplicated near the other end, each shuttle car having a mold and spin wheels and a motor to drive the spin wheels, and mean to shuttle the cars on the track between a first and'a second station, in alternation, whereby both cars may be usefully operated on simultaneously.

4. A centrifugal casting machine comprising a shuttle track with two shuttle cars thereon, a first pair of stations comprising a core setting station at one side of the track and a pouring station at the other side of the track at a point opposite the core setting station, a second pair of stations comprising a pulling station on one side of the track and a spray station on the other side of the track at a point opposite the pulling station, one pair of stations being midway between the ends of the track, the other pair being near one end and being duplicated near the other end, each shuttle car having a mold and spin wheels and a motor to drive the spin wheels, and means to shuttle the cars on the track between the core set-pour stations and the pull-spray stations, in alternation so that four of the six stations are in use at a time.

S. A centrifugal casting machine comprising a shuttle track with shuttle car means thereon, a pouring station at one side of the track midway between the ends, two pulling stations on one side of the track, one near each end, two spray stations on the other side of the track at points opposite the pulling stations, the shuttle car means having spaced molds resting on spin wheels and having motor means to drive the spin wheels, and means to shuttle the shuttle car means on the track between the pouring station and the pull-spray stations, so that three of the said five stations are in use at a time.

6. A centrifugal casting machine comprising a shuttle track with shuttle car means thereon, a core setting station at one side of the track midway between the ends, a pouring station at the other side of the track at a point opposite the core setting station, two pulling stations on one side of the track, one ear each end, two spray stations on the other side of the track at points opposite the pulling stations, the shuttle car means having spaced molds resting on spin wheels and having motor means to drive the spin wheels, and means to shuttle the shuttle car means on the track between the core set-pour stations and the pull-spray stations, so that four of the six stations are in use at a time.

7. A centrifugal casting machine for casting pipe, said machine comprising a shuttle track with two shuttle cars thereon, a pouring station at one side of the track midway between the ends, two pulling stations on one side of the track, one near each end, two spray stations on the other side of the track at points opposite the pulling stations, each shuttle car having a pipe mold and spin wheels and a motor to drive the spin wheels, and mean to shuttle the cars on the track between the pouring station and the pullspray stations in alternation, whereby both cars may be usefully operated on simultaneously.

8. A centrifugal casting machine for casting pipe, said machine comprising a shuttle track with two shuttle cars thereon, a core setting station at one side of the track midway between the ends, a pouring station at the other side of the track at a point opposite the core setting station, two pulling stations on one side of the track, one near each end, two spray stations on the other side of the track at points opposite the pulling stations, each shuttle car having a pipe mold and spin wheels and a motor to drive the spin wheels, and means to shuttle the cars on the track between the core set-pour stations and the pull-spray stations in alternation, whereby both cars may be usefully operated on simultaneously.

9. A centrifugal casting machine as defined in claim 5, in which the means to move the shuttle car means is a long hydraulic cylinder with a piston and piston rod connected thereto, and in which there are buffer means cooperating with bumpers on the shuttle car means to resiliently stop the same at each end of the shuttle travel.

10. A centrifugal casting machine as defined in claim 7, in which the means to move each shuttle car is a long hydraulic cylinder with a piston and piston rod connected to the car, and in which there are buffer means cooperating with bumper on the cars to resiliently stop the cars at each end of the shuttle travel.

11. A centrifugal casting machine as defined in claim 5, in which the shuttle car means has rollers on horizontal axes to support the same, and additional rollers on vertical axes to guide the same, and in which the shuttle track includes support tracks for the horizontal rollers and a guide track for the vertical rollers.

12. A centrifugal casting machine as defined in claim 7, in which each car has rollers on horizontal axes to support the same, and additional rollers on vertical axes to guide the same, and in which the shuttle track includes support tracks for the horizontal rollers and a guide track for the vertical rollers.

13. A centrifugal casting machine as defined in claim 3, in which each car has a pair of collateral molds and spin wheel supporting the two molds, and in which the core setting station, the pour station, the pull station and the spray station all are double stations for cooperation with the double molds on each shuttle car.

14. ,A centrifugal casting machine as defined in claim 7, in which each car has a pair of collateral pipe molds and spin wheels supporting the two molds, and in which the core setting station, the pour station, the pull stations and the spray stations all are double stations for cooperation with the double molds on each shuttle car.

15. A centrifugal casting machine as defined in claim 7, in which each car has a pair of collateral pipe molds and three spin wheels supporting the two molds, the center spin wheel being motor-driven to drive both molds,

and the outer spin Wheels being idle, and in which the core setting station, the pour station, the pull stations and the spray stations all are double stations for cooperation with the double molds on each shuttle car.

16. A centrifugal casting machine as defined in claim 3, in which the pull mechanisms are supported and operated at a level higher than the mold level, and in which there are receiving means below the pulling station to receive the casting pulled from the mold at the pull station.

17. A centrifugal casting machine as defined in claim 5, in which the pull mechanism are supported and operated at a level higher than the mold level, and in which there are receiving means below the pulling station to receive the casting pulled from the mold at the pull station.

18. A centrifugal casting machine as defined in claim 7, in which the pull mechanisms are supported and operated at a level higher than the mold level, and in which there are pipe receiving means below the pulling station to receive pipes pulled from the mold at the pull station.

References Cited UNITED STATES PATENTS 1,595,119 8/1926 Paige 164-295 1,936,376 11/1933 Camerota 164-295 2,731,690 1/1956 Coupland et al 164-114 2,948,933 8/1960 Molloy et al. 164-299 3,111,729 11/1963 Clay 164-295 3,171,171 3/1965 Farr et a1. 25-30 3,225,891 12/1965 Hickin et al. 198-31 2,859,502 11/1958 Brown 25-41 2,985,931 5/1961 Frankenstein 164-38 FOREIGN PATENTS 1,332,166 6/1963 France.

I. SPENCER OVERHOLSER, Primary Examiner.

R, D. BALDWIN, Assistant Examiner. 

1. A CENTRIFUGAL CASTING MACHINE COMPRISING A SHUTTLE TRACK WITH SHUTTLE CAR MEANS THEREON, A FIRST STATION HAVING METAL POURING MEANS AT ONE SIDE OF THE TRACK, A SECOND STATION COMPRISING PIPE PULLING MEANS ON ONE SIDE OF THE TRACK AND A MOLD SPRAY MEANS ON THE OTHER SIDE OF THE TRACK AT A POINT OPPOSITE THE PIPE PULLING MEANS, ONE STATION BEING MIDWAY BETWEEN THE ENDS OF THE TRACK, THE OTHER STATION BEING NEAR ONE END AND BEING DUPLICATED NEAR THE OTHER END, THE SHUTTLE CAR MEANS HAVING SPACED MOLDS RESTING ON SPIN WHEELS AND HAVING MOTOR MEANS TO DRIVE THE SPIN WHEELS, AND MEANS TO SHUTTLE THE SHUTTLE CAR MEANS ON THE TRACK BETWEEN A FIRST AND A SECOND STATION. 